Depends on the condition of the Invernos. If they are in okay condition, keep the Invernos for Elberus and any other multi-day expedition climbs. Double boots are nice in the morning when it's 20 below. New liners could boost the warmth of these boots. Get the Nepals for Colorado and Rainier and any day stuff.

Good advice from the previous post. I would sport the Inverno's on Elbrus if you're worried about cold (no experience there, but I hear it can get super cold) and pick up a pair of Nepal's. They are an awesome boot and super versatile and will definitely work on Rainier and MX. They are good for most pursuits in the lower 48 for that matter, I wear them in the Sierra year round.

Do your feet tend to be cold? Do you do overnight trips? Although not everything you're talking about, my Nepals were not keeping my feet warm enough on Colorado winter 14ers and igloos trips. I just bought a pair of LS Baruntse and love them. Took them ice climbing for the first time and they worked great for that as well and my feet were warm standing around in 5 degree weather while the folks in Nepals were all freezing.

Cos what you buy might depend on what you do beyond this year. I agree Nepals might not be warm enough for Elbrus, from what I've heard of there, though fine for Rainier and Orizaba, and maybe OK with -40Below overboots, so long as you can put them on warm in the hut and your crampons fit over them. Baruntses would be a lot better for Elbrus, and not too much overkill on Orizaba or Rainier.

Spantiks are great boots, but overkill for anything in the Lower 48 or Mexico, and you've already done Denali. They'd just get trashed on Aconcagua, in case you're thinking of that, and they're not really warm enough for an 8000er, especially Everest, and they're not nimble enough for ice or technical climbing at home. So you probably don't want Spantiks.

Dane's coldthiste.blogspot has heaps of info on Baruntse vs. Spantik. They seem like a good intermediate step for most people between single boots and Everest boots.

Incidentally, almost all modern boots (not looked at the newest Scarpas) are actually way too stiff and technical for what many climbers are doing, which is mostly hiking. Nepals are good boots for technical ice and mixed climbing where you want stiffness for frontpointing. They are not the best boots for comfy hiking, and Rainier, Orizaba and Elbrus are all hiking - just hiking in snow and low-angle ice. There are other (single) boots out there that may be more suitable for what you, and most people, are doing than Nepals.

Damien Gildea wrote:and they're not nimble enough for ice or technical climbing at home. So you probably don't want Spantiks.

That's simply not true. Granted, if it's super technical stuff WI5+/6, yes, you might want something lighter and lower profile. For the general climbing population, they are more than capable of climbing technical stuff.

My partner wore LS Nepal on Rainier in May, Elbrus in June, Ixta & Orizaba in November. All these peaks at their extreme can be very cold but when I was on Elbrus in June, there were Russian dudes in their Speedo and the chicks were in their sport spa at 15k' trying to get a tan after taking the snowcat up.

For multi-day trips, it's nice to be able to dry out your inner boots.

You might want to look at the Scarpa Omegas. They are lighter than most of the boots you are considering, and you can take the inner boots out at night to dry them. They are comfortable to walk in, and flexible enough for French technique.

If you don't go with the double boot option, I'd suggest a VBL sock for multi-day climbs in single boots.